1. Field of the Invention
This invention relates to an operation control device for a camera which is capable of accomplishing focus lock photography.
2. Related Background
There is known a camera which is capable of accomplishing so-called focus lock photography in which distance information is memorized, for example, along with the half depressing operation of a release button and even if framing is changed thereafter, when the release button is fully depressed, a photo-taking lens is driven to the focusing position on the basis of the memorized distance information and shutter release is effected.
There is also known a camera in which in response to the half depressing operation of a release button, a photo-taking lens is driven to the focusing position on the basis of the then distance information and is fixed at that position and shutter release is effected along with the full depressing operation of the release button. The distance information is information indicative of the distance to an object, but there is also known a camera in which a photo-taking lens is driven to the focusing position on the basis of focus adjustment information indicative of the amount and direction of deviation between the imaging plane of an object image and the predetermined imaging plane and which effects such focus lock.
However, in such prior-art cameras, focus lock is released upon release of the half depressing operation and therefore, when one requests a third person to photograph, one cannot hand the camera over to the third person while holding the state of the focus lock. Accordingly, if the third person requested to photograph does not know focus lock photography, the photo-taking lens will not be in focus to the main object and an undesired photograph will be taken when the main object is not positioned within an auto focus frame in a viewfinder.